Sister, apprehensive initially, in college in Warwickshire town (8)
I believe the answer is:
nuneaton
'warwickshire town' is the definition.
(I've seen this before)
'sister apprehensive initially in college' is the wordplay.
'sister' becomes 'nun' (I've seen this before).
'initially' indicates taking the first letters.
'in' is an insertion indicator.
'college' becomes 'eton' (I've seen this before).
The first letter of 'apprehensive' is 'a'.
'a' inserted within 'eton' is 'eaton'.
'nun'+'eaton'='NUNEATON'
'in' acts as a link.
(Other definitions for nuneaton that I've seen before include "Warwickshire town" , "northern English town" , "midlands town" .)